Tumbler lock with axially shiftable interchangeable tumblers



Sept. 3, 1963 w. s. CHRISTOPHER 3,102,412

TUMBLER LOCK WITH AXIALLY SHIFTABLE INTERCHANGEABLE TUMBLERS Filed 001;.25, 1961 //v VENTOR: WALTER 5. CHRISTOPHER ATT'X United States Patent3,102,412 TUMBLER LOCK WITH AXIALLY SHIFTABLE INTERCI-IANGEABLE TUMBLERSWalter 5. Christopher, Park Ridge, Ill., assignor to Chitlrggo LockCompany, Chicago, 11]., a corporation of axons Filed Oct. 23, 1961, Ser.No. 146,778 1 Claim. (Q1. 70-363) The present invention relates toimprovements in tumbler locks and has particular reference to tumblerlocks of the type wherein the various tumblers associated therewith areaxially shiftable with respect to the lock cylinder. In a lock of thisgeneral type, the tumblers slide in bores and pass from the stationarypart of the lock into the rotatable part. Furthermore, the tumblers aretransversely divided or split and are adapted to be longitudinally oraxially displaced by the proper key for the lock against the resistanceof springs in such a manner that their splits or joints coincide withthe joint between the movable and stationary parts of the lock. For thatpurpose, the key which controls the lock is provided with an annularseries of push pins or other protuberances of unequal but definite orpredetermined length, the various lengths of the push pins beingcommensurate with the extent to which their associated or respectivetumblers must be forced back into the pinreceiving bores of the lock sothat all of the joints of the tumblers will conicide with the jointbetween the stationary and rotatable parts of the lock and thus permitthe rotatable part to be turned by the key.

In my copending patent application Serial No. 127,584, filed on July 28,1961, and entitled Adjustable Key and Assembly Jig Therefor, there hasbeen disclosed a key for locks of the character briefly outlined aboveand wherein the push pins are interchangeable in their respectivemountings to the end that the number of effectively different keys whichmay be constructed for use with difierent combinations of tumblers,while utilizing the same key parts, will be governed by the mathematicallaw of all possible permutations. The key is designed primarily for usein elfecting quick and easy changeover operations as, for example, bythe field operator of public vending machine cabinets where thechange-over may be made at the scene of any given installation andwithout requiring either the services of a work bench or special tools,as well as dispensing with the necessity of conducting extensivedismantling operations of the key assembly. The present tumbler lock hasbeen designed as a counterpart of the key shown and described in thehereinbefore mentioned patent application in that it also is capable ofquick and easy change-over operations by a field operator. Thus, whenemployed as a vending machine cabinet lock, for example, the same fieldoperator, at the time he efiects a change-over of the key combination,may also effect a commensurate or corresponding change-over operation onthe counterpart look so that the combination of both the lock and keywill agree and become effective for cabinetlocking and unlockingoperations, both change-over operations being readily performed in thefield at the scene of the installation and without requiring extensivedismantling of either par-t.

Present day changeable combination locks of the character underconsideration herein are possessed of at least one serious limitation inthat it is extremely difficult to effect a change-over operation of thecombination in the field. Ordinarily, it is necessary to remove the lockfrom its mounting and to thereafter remove the core or barrel from thelock cylinder and otherwise almost completely dismantle the assembly.Not only are special tools required for these dismantling operations,but a 3,i2,4l2 Patented Sept. 3, 1963 suitable work bench or table isnecessary. It also is desirable that a container or tray be provided tohold the parts while the lock assembly is dismantled.

The present invention is designed to overcome the above-noted limitationthat is attendant upon the con struotion and use of conventionalchangeable combination tumbler locks and, accordingly, it contemplatesthe provision of a novel lock assembly having axially shiftable splittumblers which are longitudinally slidable in the lock cylinder and inwhich the tumblers are removable from the cylinder in which they areslidable through the rear end of the latter so that it is not necessaryto remove the cylinder from the barrel in which it is rotatable. Sincethe tumblers are removable through the rear end of the barrel, and sincethe latter is normally exposed on the inside of the door or other panelon which the lock is installed, it is not essential that the cylinder,i.e., the entire lock assembly, be removed from its mounting whenchange-over operations are effected.

The provision of a tumbler lock wherein change-over operations may beeffected in a simpler manner and with considerably greater dispatch thanhas heretofore been possible with other locks designed for the samepurpose being among the principal objects of the invention, it is afurther object to provide such a lock wherein the only tool required forelfecting the change-over operation is a pair of jewelers tweezers or asimilar tool.

The provision of a lock of this character which is comprised of aminimum number of pants and which, therefore, is unlikely to get out oforder; one which is rugged and durable and which, therefore, willwithstand rough usage; one which is simple in its construction andwhich, therefore, may be manufactured at a low cost; and one whichotherwise is well adapted to perform the services required of it, arefurther desirable features which have been borne in mind in theproduction and development of the present invention.

In the accompanying single sheet of drawings forming a part of thisspecification, one illustrative embodiment of the invention has beenshown.

In these drawings:

FIG. 1 is a perspective view of an adjustable key designed forcooperation with the adjustable lock of the present invention;

FIG. 2 is a front perspective view of the adjustable lock;

FIG. 3 is a rear end elevational view of the lock;

FIG. 4 is afragmentary sectional view taken substantially along the line44 of FIG. 3;

FIG. 5 is a sectional view similar to FIG. 4, with a portion of the'view being exploded and, with other portions being broken away, andillustrating the manner in which change-over operations may be effected;and

FIG. 6 is a rear elevational view of the lock with certain portionsbroken away to more clearly reveal the nature of the invention.

Referring now to the drawings in detail, a lock constructed inaccordance with the principles of the present. invention has beendesignated in its entirety at 10 and it includes a lock cylinder 12within which there is disposed a sleeve-like rotatable part 14 and anon-rotatable sleeve-like part 1-6. The fixed part :16 is maintainedwithin the cylinder 12 against relative rotation by means of a radialpin 17 (see FIG. 4). An annular series of split tumblers 18, eachincluding a driver pin 20 and a spring-pressed follower pin 22, areslidable longitudinally in respective bores in the two parts. Thetumblers are adapted to be longitudinally displaced by the key which hasbeen shown in FIG. 1 and designated in its entirety at 24 and when theyare so displaced'that all of the joints or splits 26, therefore, are intransverse register with the interfacial plane between the two par-ts,

3 the rotatable part 14 may be turned within the lock cylinder in theusual manner of key operation. The splits are at different longitudinallocations.

The lock cylinder has an inwardly extending front flange 30 which isprovided with a radial notch 32 for entry of an external guide lug 34 onthe key 24, and a diametrically opposed radial notch 36 for removal ofthe guide lug "34 and withdrawal of the key when the rotatable part 14has been turned in its unlocked position. A pilot post 38 is movablewith the rotatable part 14 of the lock and cooperates with the key 24 ina manner that will be made clear presently in order to facilitate properentry of the key 24 into the lock cylinder.

Reference may be hadto the above-mentioned patent application Serial No.127,584 for a full disclosure of the construction and operation of thekey 24 of FIG. 1, but for purposes of description herein and to show therelationship which the key bears to the lock it is deemed suflicient tostate briefly that the key involves in its general organization anannular series of push pins 48 for actuating the tumblers 1-8 of thelock 10. The push pins 40' are of unequal length and they are adapted tobe selectively and interchangeably received in a series oflongitudinally extending grooves 42 provided in the outer surface of acylindrical tubular push pin holder 44. The pins fit snugly within thegrooves 42 and, when assembled therein, the holder and pins are receivedwithin a socket provided in the cylindrical body portion 46 of the key.They are locked in position within the socket by means of a fasteningbolt 48. An internal drive lug 50 on the holder cooperates with a notch52 in the pilot post 38 as a preliminary to unlocking the lock 10. Afterinsertion of the key into the lock, the lug 50 and the notch 52 form adriving connection whereby the key and rotatable part 14 are lockedtogether for conjoint turning movement.

The various push pins 40' are of unequal length and, consequently, theyare positioned within the grooves 4 2 with the forward ends thereofbeing positioned at different longitudinal distances from the forwardrim of holder 44. Thus, when the key is inserted into the lock, the endsof the push pins engage the forward ends of the split tumblers 18 andslide the tumblers rearwardly into their lock-releasing position whereintheir splits coincide with the interfacial plane between the rotary andstationary lock parts 14 and 16., respectively, and then permit therotatable part to be turned by the key relatively to the stationarypart.

As previously stated, the various push pins 40 are interchangeable inthe grooves 42 and, in order to effect change-over operations, in; ismerely necessary to remove the fastening bolt 48 and slide the holder 44and its contained push pins 40 from the socket provided in thecylindrical body portion 46'. The push pins 40 are then in an exposedposition whereby they may readily be selectively interchanged accordingto any desired contemplated permutation.

It is obvious that when a given change-over has been made in thearrangement of the push pins 40 of the key 24, a correspondingchange-over must be effected upon the tumblers 18 of the lock 10'.According to the present invention, such a change-over operation may beeffected in a simple and easy manner by reason of the way in which thetumblers 18 are made accessible for removal from the rear end of thelock cylinder 12. Accordingly, the rear open rim region of the cylinder12 is formed with an internal narrow annular groove 60 within whichthere is adapted to be seated a removable expansible and contractiblesplit locking ring 62, which, when in position within the groove, servesto maintain a backing ring 64 in position within the central bore 66within which the rotatable and non-rotatable parts 14 and 16,respectively, are mounted. The backing ring 64 is provided for thepurpose of assimilating the reaction force of a series of springs 68 bymeans of which the split tumblers 18 are forced forwardly withinrespective small bores 70 and 72 provided in the parts 14 and16,,respeotively. In the locked condition of the lock 18, the variousbores 70 and 72 remain in axial alignment or register but with thevarious splits 26, or at least one of them, out of register with theinterfacial plane between the two parts :14 and .1 6. In the unlockedcondition of the lock 10, all of the splits 26 are in circumferentialalignment with one another, as well as with such interfacial plane, asis customary with locks of the axially movable tumbler type. The springs68 serve to move the various tumblers 18 forwardly within the alignedbores 70 and 72 when the latter are in respective alignment.

The previously mentioned pilot post 38 forms part of a central plug 74which projects rearwardly beyond the rear rim of the cylinder 12 and isprovided with a reduced extension 76 having flattened sides 78, thereduction in diameter affording an annular rearwardly facing shoulder 80on the plug 74. A stop cam 82 seats against the shoulder 80 and has apair of oppositely directed shoulders 84 and 86 (see FIG. 6) designedfor engagement with a stop lug 88 formed on the cylinder 16 to limit theextent of rotational movement of the rotatable lock parts in oppositedirections respectively. A lock washer 90 is disposed forwardly of thestop lug 88 and a radially extending locking plate 92 is carried on theextension 76 rearwardly of the lock washer 90. A nut 94 is threadedlyreceived on the extension 76 and serves to maintain the stop cam 82,washer 90 and locking plate- 92 in position on the threaded extension76. The extension is .formed with oppositely facing flat sides 78 and afiat sided recess 98 is formed in the locking plate for reception of theextension so that relative turning movement between the two parts isprecluded. The locking plate 92 thus receives its turning movement underthe influence of the key 24 which drives the plate through the medium ofthe cooperating drive lug 50', notch 52, pilot post 38 and pl g 74.

When it is desired to eifect change-over operations on the lock 10, itis merely necessary for the operator to remove the nut 94 and lift thelocking plate 92 from the end of the extension 76 on the plug 74 afterwhich, by the aid of a pair of tweezers or pliers of the needle nosevariety, to contract the split locking ring 62 and withdraw the samefrom the groove 60 so as to release the backing ring '64 which also maybe withdrawn from the cylinder 12. To facilitate removal of the lockingring 62, the adjacent ends thereof in opposite sides of the splittherein are enlarged and provided with entry holes 100 for reception ofthe ends of the tweezers or pliers jaws preparatory to contraction ofthe ring. After the backing ring 64 has been removed, the ends of thevarious springs 68 are exposed from the rear open end of the lock andthey may be pulled from their respective bores 72, utilizing the sametool which was employed for releasing the split locking ring 62. Uponremoval of the springs 68, the follower pins 22 are accessible forremoval and, thereafter, access may be had to the driver pins 20.

In thus removing the tumblers 18 for interchange purposes, the entirelock assembly may be removed from the cabinet door or other installationwith which it is incorporated, but it is not essential that such removalbe effected. The lock cylinder may be left in position in theinstallation and, after the springs 68 have been withdrawn from the lockcylinder 12, the tumblers may be rendered accessible through the rearopen rim of the cylinder simplyby inserting the point of the toolthrough the open front rim of the cylinder and pushing the tumblersrearwardly so as to expose the rear ends thereof.

It has been previously stated that change-over operations ordinarilywill be made upon a key 24 and its mating lock 10 by the same operatorat the scene of installation. It is obvious that when such a dualchange-over operation is made, the position to which any given push pin40 in the key 24 has been moved must be accompanied by a correspondingpositioning of the corresponding tumbler in the lock. To assist theoperator in effecting such correlation between push pins and tumblers,colored indicia may be employed on the pins and tumblers, for example,by the application of daubs of identically colored lacquer to the pinsand tumblers which correspond to each other. It is not necessary toremove all of the tumblers at one time in effecting a change overoperation. As soon as one tumbler has been removed, another tumbler maybe extracted from the cylinder and deposited in the place originallyoccupied by the first removed tumbler. Thus, at no time is the operatorobliged to keep track of more than the parts associated with theparticular tumbler with which he is dealing at any given instant.

The invention is not to be limited to the exact arrangement of partsshown in the accompanying drawing or described in this specification asvarious changes in the details of construction may be resorted towithout departing from the spirit of the invention. Therefore, onlyinsofar as the invention has particularly been pointed out in theaccompanying claim is the same to be limited.

Having thus described the invention what I claim as new and desire tosecure by Letters Patent is:

In a tumbler lock of the character described, a lock cylinder having anaxial bore extending therethrough and provided with an open front rimfor insertion of a key therethrough and an open rear rim, an annularsleeve-like front rotatable part and an annular sleevelike fixed partdisposed within said bore and presenting relatively slidable faces whichmeet each other on an interfacial plane normal to the axis of thecylinder, a plug projecting through said rotatable and fixed parts andhaving a portion thereof extending rearwardly outwardly through the1OPI1 rear rim of the cylinder, means securing the plug and rotatablepart together for rotation in unison, a series of longitudinallyextending bores termed in said fixed part and arranged incircumferentially spaced relationship therearound, a similar series oflongitudinally extending bores tformed in said rotatable part andsimilarly arranged therearound, said rotatable part being movablebetween a position wherein the respective bores of the two parts are inalignment and the lock is in its locked condition and a position.wherein such bores are out of alignment and the lock is in its unlockedcondition, a split tumbler assembly for each pair of aligned boresincluding a driver pin slidable in the respective bore of the rotatablepart and a follower pin slidable in the respective bore of the fixedpart, a spring disposed in each bore of the fixed part rearwardly of theifollower pin therein for normally urging the latter rforwardly, therearwardly extending portion of the plug being of reduced diameter andthus defining a rearwardly facing shoulder on the plug, a stop camsurrounding the rearwardly extending portion of the plug and seatingagainst said shoulder, said stop cam being disposed exteriorly of thecylinder and rear-wardly of the backing ring, said stop cam beingprovided with a pair of ciroumferentially opposed stop shouldersthereon, a stop lug formed on the rear end face of the cylinder andinterposed between said stop shoulders on the stop cam, a backing ringdisposed within said bore in the cylinder rearwardly of said springs forassimilating the rearward thrust of the latter, said bore in thecylinder being formed with an internal annular groove therearoundadjacent to the rear rim thereof, and a removable split locking ringdisposed within said groove and having its inner periphery projectinginwardly of the bore, the radial extent of said backing ring beinggreater than the radius of said inner periphery of the locking ringwhereby the backing ring is effectively retained within the bore in thecylinder when said locking ring is in position within said groove.

References Cited in the file of this patent UNITED STATES PATENTS1,968,555 Home July 31, 1934 2,557,028 Deutsch June 12, 1951 2,993,361Van Lahr July 25, 1961 FOREIGN PATENTS 504,473 France Apr. 15, 1920424,800 Italy Sept. 2, 1947 445,596 Italy Feb. 18, 1949

